I designed these bellows as part of a modification to adapt the Gaggia MDF grinder to single dosing.

The rest of the modifications are here: https://www.thingiverse.com/thing:4208625

Printed in TPU. No supports required when printed as oriented in the STL (flat top on the print base) and using 'make overhang printable' with 50 degree angle in cura. I may rework the angles in the model at some point in the future. I didn't use infill as I wanted to maintain flexibility in the bellows, but had to set bottom thickness to 2mm to get the flat bit to print solid. It did take some tweaking to get this looking good.

Enjoy!